I actually think this is encouraging. In previous games the offense was much less effective after the half. Arians
scripts out 30 plays (basically a half's worth), 15 passes, 15 runs, and his QB picks the passes, so presumably Brady was picking the stuff he's more comfortable with, and they were struggling once they got out of that set of plays. The second-half success yesterday I think indicates more of a comfort level with the whole offense.
It's easy to forget that it was really a tale of two offenses last year. The first half, the passing O was pretty good and the run game was awful. The second half, the passing O was lousy and the run game was OK. Injuries factored pretty heavily into both (Wynn and the FBs the first half; Gordon, Brady, Edelman, Sanu the second)